Aquarium tank



FIG. 1 is a top and right front perspective view of an aquarium tank, showing my new design;

FIG. 2 is another perspective view showing the cover open;

FIG. 3 is a a top, rear and left side perspective view thereof;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a right side elevational view thereof, the left side being shown in FIG. 3.

The bottom is plain and unornamental. 

The ornamental design for an aquarium tank, as shown and described. 